Small Electrical Appliance And Electric Motor Drive Unit For A Small Electrical Appliance

Abstract

A small electrical appliance is disclosed. The small electrical appliance includes a head element which carries out a rotational movement and a translational vibration movement; a housing; an electric motor drive unit in the housing, with a first output for generating a rotational movement relative to the housing, which includes at least a first component of the electric motor drive unit, and a second output for generating a translational vibration movement relative to the housing, which includes at least a second component of the electric motor drive unit; a shaft which is connected to the first component of the electric motor drive unit in order to transmit the rotational movement to the head element; and a rocker which is connected to the second component of the electric motor drive unit in order to transmit the translational vibration movement to the head element.

1 . A small electrical appliance, comprising
 a head element which carries out a rotational movement and a translational vibration movement;   a housing;   an electric motor drive unit in the housing, with a first output for generating a rotational movement relative to the housing, which includes at least a first component of the electric motor drive unit, and a second output for generating a translational vibration movement relative to the housing, which includes at least a second component of the electric motor drive unit;   a shaft which is connected to the first component of the electric motor drive unit in order to transmit the rotational movement to the head element; and   a rocker which is connected to the second component of the electric motor drive unit in order to transmit the translational vibration movement to the head element;   wherein the first component and the second component are decoupled in such a way that the first component does not follow the vibration movement of the second component.   
     
     
         2 . The small electrical appliance according to  claim 1 , wherein the first component and the second component have no rigid mechanical connection. 
     
     
         3 . The small electrical appliance according to  claim 1 , wherein the first component and the second component include permanent magnets which can move independently of one another in the field of an electromagnetic coil. 
     
     
         4 . The small electrical appliance according to  claim 1 , further comprises a buffer between the housing and the rocker. 
     
     
         5 . The small electrical appliance according to  claim 1 , wherein the rotational movement is a rotational vibration movement. 
     
     
         6 . The small electrical appliance according to  claim 1 , wherein the at least one head element is a brush head for an electric toothbrush. 
     
     
         7 . An electric motor drive unit for a small electrical appliance, comprising:
 at least one first and at least one second vibratable component;   a coil for generating a magnetic field;   a first magnet arrangement which includes at least one first permanent magnet which, in cooperation with a magnetic field generated by the coil, generates a force for inducing a rotational vibration of the at least one first vibratable component;   a second magnet arrangement which includes at least one second permanent magnet which, in cooperation with a magnetic field generated by the coil, generates a force for inducing a linear vibration movement of the at least one second vibratable component; and   at least one flux conducting element which is arranged in such a way that it conducts magnetic flux generated by the coil to interact with the at least one second permanent magnet;   
       wherein the at least one flux conducting element includes a metal yoke which passes through the coil windings. 
     
     
         8 . The electric motor drive unit according to  claim 7 , wherein the at least one flux conducting element follows the movement of the at least one first vibratable component. 
     
     
         9 . The electric motor drive unit according to  claim 7 , wherein the linear vibration movement is perpendicular to the axis of rotation of the rotational vibration movement. 
     
     
         10 . The electric motor drive unit according to  claim 7 , wherein the at least one first and the at least one second vibratable components have different resonant frequencies (f R , f L ). 
     
     
         11 . The electric motor drive unit according to  claim 7 , wherein the at least one first vibratable component, the first magnet arrangement and the coil are configured in such a way that a reluctance torque which acts after the coil current has been switched off and which causes an angular movement of the first vibratable component acts as a return torque. 
     
     
         12 . The electric motor drive unit according to  claim 7 , wherein the at least one flux conducting element, the second magnet arrangement and the coil are configured in such a way that a reluctance torque which acts after the coil current has been switched off and which causes a linear movement of the second vibratable component acts as a return torque.